Shelf life of Vitamin C

[skin101]

Hi Sarah,

What is the shelf life of Vit C (L-Ascorbic Acid). I bought it last year (Oct, 2011) and I still have 2 packs.
Can I still use them?

Thanks.

[SarahVaughter]

The shelf life of vit. C crystals is three years but in reality they will keep even longer.

Vit. C becomes unstable in a watery solution and that is why the vit. C serum has to be made fresh frequently, whereas the crystals themselves are stable.

You should keep them cool, dry, dark, and in a closed container (close the ziplock bag).